If the "money question" is asked early in the interview (as it often is), the best response is: "What would a person with my background and qualifications typically earn in this position with your company?" The best response if asked late in the interview process is: "I am ready to consider your very best offer." This is one time you don't want to be specific. If you give specifics, you lose--you will either be too low or too high, costing yourself thousands of dollars or possibly even keeping yourself from getting the job.
That said, if you are pressed by the interviewer for specific numbers, don't put them off with more than one "end run" response. First, make sure you have done your homework on the expected salary range for your field. The salary surveys usually are skewed toward the high end (possibly because only the best paid graduates responded, while those with average or low pay did not want to admit what they were earning), so take them with a large dose of conservative adjustment. The best surveys are from those who graduated within the last year in your major from your school. You can possibly locate such information through your Career Center, Alumni Office, or your personal network of contacts. A business grad from Stanford is going to be earning a lot more than a business grad from Podunk U. Know the "going rate" for your major, your school, and the field that you are considering entering. And make sure you know it before you get propositioned with the money question.
Armed with this information, ask the interviewer: "What is the general salary range for new hires in this position?" If the entire range is acceptable, respond with: "That would be within my expected starting range, depending on the entire salary and benefits package." If only the top end of the range is acceptable, respond with: "The upper end of the range is what I have been discussing with the other companies that are currently interested." If the range is below your expected starting salary range (be careful!), respond with: "The other companies I am currently speaking with are considering me at a salary somewhat higher than that range. Of course, money is only one element and I will be evaluating the overall package." Do your best not to get pinned to specific numbers, but if they do mention a number and ask if it would be acceptable to you, respond by saying: "I would encourage you to make the formal offer. What is most important is the opportunity to work for you and your company. I am confident that your offer will be competitive." Remember, don't do any negotiating until you have a formal offer in hand.